Stable surface alloy steel



Patented Dec. 29, 1931 UNITED STATES PATENT OFFICE RALPH 1?. DE 'VRIES, OF NEWTONVILLE, NEW YORK, ASSIGNOR TO LUDIIUM STEEL COM- PANY,.OF WATERVLIET, NEW YORK, A CORPORATION OF NEW JERSEY STABLE SURFACE A LLOY STEEL No Drawing.

This invention relates to alloys of steel, and more particularly to such alloys as are known to the trade as stable-surface alloy steels.

The main objects of my invention are to provide an alloy steel of new composition which will be resistant to scaling action at high temperatures ranging from a low red heat to temperatures as high as 1800 F., and which will be resistant in varying degrees to rusting acids,and corroding agents of various kinds. This steel may be readily forged and rolled, and when it has been thus forged and rolled, it will have good strength and fair ductility.

The invention is especially useful where steels are to be used for internal combustion engine poppet valves, electrical resistance heating. elements, carburizing boxes, and for other purposes wherein metal is desired which will resist scaling, particularly at high temperatures.

An alloy steel containing as its essential elements carbon and silicon within the ranges of my present invention, with iron as the balance of the alloy, has fairly good resistance to scaling and towards action of corroding agents of various kinds. When such an alloy however, contains percentages of silicon, which run above 2 to 3% it becomes decidedly interior with re ard to its physical strength and ductility. percentages of silicon than 2 to 3% are used, the alloy becomes useless for most structural, and engineering purposes.

I have discovered that copper may be added to such an alloy in substantial amounts and that when so added it produces a steel having the desired qualities of strength and ductility, as well as resistance to scaling at high temperatures. Such steels containing percentages of silicon as high as 6% may then be readily forged, rolled or worked,

in any manner desired, and have when thus forged or rolled, the desired characteristics mentioned above.

An alloy steel made in accordance with my invention contains from 2.0% to 7.0% of silicon and from 0.50% to 6.0% of copper. Alloys of my invention when made with the ien much higher V Application filed January 20, 1926. Serial No. 82,607.

structuralsteels may be present, or slightly greater amounts up to 1.5% may be used. Impur1t1es and metalloids, such as sulphur, phosphorous, etc, will be kept as low as possible. Typical examples of this alloy may be noted as having the following composition, the iron balance including the manganese, impurities and metalloids mentioned above:

Carbon Copper Silicon Iron 0. 257 3. 5'7 3. 5] Balance 0. 30% 1. 5% 5. 2% Balance It is a well known fact that silicon in the highest proportions herein mentioned ordinarily makes a very coarse grain alloy of very little strength. The copper in the present alloy overcomes this objection. It produces an alloy which can be forged, and whlch has good strength. For still further refining the grain, titanium may be added in amounts running from as low as 0.1% up to 5.0%. Where it is desired to impart greater strength to the alloy which is to be sub ec-ted to igh temperatures, I may add tungsten or molybdenum in percentages 0.5% to 5.0%.

Alloy steels made in accordance with my invention can be readily hardened by heating above their critical ranges and then cooling in water, oil, or airas desired. For many purposes for which this alloy steel is adapted, it will be desirable to vary'the physical properties by heat treatment which may consist of hardening as mentioned and drawing the steel by re-heating after such hardemng.

I claim 1. A ferrous alloy consisting of from over 2% to 7% of silicon, from over 0.5% to 6% of copper, up to 1.5% manganese and the balance iron.

2. An alloy steel consistingof from more than 2% to 7% of silicon, from 0.5% to 6% of copper and the balance iron with the usual manganese.

3. In an alloy steel composed of from over 2% to 7 of silicon, copper in suificient quantity between the proportions of 0.5% and 6% to render the product malleable both hot and cold and the balance iron with the usual manganese.

4. An alloy. steel composed of from 2.5% to 7% of silicon, copper in suflicient quantity between the proportions of 0.5% and 6% to render the product malleable both hot and cold and the balance iron with manganese up to 1.5%.

In testimony whereof I have name to this specification.

RALPH P. DE VRIES.

signed my 

